JP2003252888A - Organic iridium complex and organic electroluminescent element using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve emission efficiency of an organic electroluminescent element and sufficiently ensure driving stability in the organic electroluminescent element using phosphorescent emission. <P>SOLUTION: An organic iridium complex is expressed by general formula (i) (wherein m expresses numbers of a ligand L and is 0, 1 or 2; L expresses an arbitrary bidentate ligand; the ring A expresses a 5 membered heterocycle having ≥1 hetero atoms and may have a substituent; the ring B expresses N-containing 5 membered aromatic heterocycle and may have a substituent; a fused ring including the ring A and the ring B may be formed by mutually bonding a group included in the ring A and a group included in the ring B; an arbitrary substituent is bonded to the carbon in the α-position to the hetero atom included in the ring A and the ring B). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an organic iridium complex useful as a novel phosphorescent dye, and more particularly to an organic electroluminescent device used in a thin film type organic EL device or a near infrared light emitting material. .

[0002]

2. Description of the Related Art Up to now, many fluorescent dyes have been used in organic electroluminescent devices, but they are used as displays for flat panel displays, light sources such as fluorescent lamps and marker lights, and near-infrared light emitting materials. In order to apply it, it is necessary to further improve the luminous efficiency of the device, and development of a new light emitting material is required.

In recent years, as one of the attempts to improve the luminous efficiency of the device, the use of a phosphorescent dye utilizing the light emission from the triplet excited state, that is, phosphorescence has attracted attention. This is because when phosphorescence is used, the extraction efficiency can be about three times as high as that of the conventional emission (fluorescence) from the singlet excited state, and high efficiency can be expected. In fact, the organic iridium complex (4) represented by the structure below was doped with 4,4′-di (N-carbazolyl) biphenyl (CBP), which emitted green light with an emission wavelength of 510 nm, and the external quantum The efficiency is 13% and the quantum efficiency limit value (5
%) Has been reported (Appl. Phys.
Lett., Vol. 75, Item 4, 1999).

[0004]

[Chemical 4]

Further, by using a compound (5) prepared by introducing various substituents into the above compound, the self-quenching of phosphorescence between the complexes can be controlled (Adv. Mater., 2001, 13, 1
245), and it is also reported that the emission wavelength can be tuned. (Chem. Commun., 2001, 1494, Appl. P
hys. Lett., 2001, 79, 449)

[0006]

[Chemical 5]

Recently, Thompson et al. Have developed various organic iridium complexes by a simple method for synthesizing iridium complexes via binuclear complexes, and have achieved organic electroluminescence devices of blue to red colors. For example, when the compounds (6) and (7) shown below are used, an electroluminescent device which emits light at a wavelength longer than that of green and has higher efficiency than a conventional singlet light emitting device can be obtained. Have been clarified (I
norg. Chem., 2001, 40,1074, J. Am. Chem. Soc., 200
1, 123, 4304., WO 01/41512).

[0008]

[Chemical 6]

Further, it has been clarified that blue light can be emitted by using the compound (8) (Appl. P.
hys. Lett., 2001, 79, 2082).

[0010]

[Chemical 7]

[0011]

[Problems to be Solved by the Invention] However, organic E
Further adjustment of color purity and improvement of light emission efficiency are required for practical application to L element materials and the like. Above all, regarding light emission in the long wavelength region, the above two points are considered to be essential. . In view of the above situation, the present inventor uses a bidentate ligand in which five-membered rings are linked to each other as an iridium ligand, so that the emission wavelength length increases as the HOMO-LUMO band gap of the ligand decreases. Wavelength conversion, color purity improvement,
We thought that we could expect high efficiency. As the organic iridium complex having a bidentate ligand in which 5-membered rings are linked, the following compound (9)

[0012]

[Chemical 8]

Has already been reported by Thompson et al. (J. Am. Chem. Soc., 2001, 123, 4304.), but since the unsubstituted thiophene ring contained in the ligand is reactive,
It is considered unsuitable when considering the prolongation of the life of the organic electroluminescence device. Therefore, in view of the above situation, the present inventor has
In particular, as a result of intensive studies aimed at improving the color purity in long-wavelength light emission, improving efficiency, and prolonging the life of the device, as a result, a substituent other than a hydrogen atom was introduced at the α-position of the heteroatom contained in the 5-membered heterocyclic ring. By doing so, they have found that the above problems can be solved, and completed the present invention.

[0014]

Means for Solving the Problems The present inventor has conducted extensive studies, and has a 5-membered ring-5 having a substituent other than a hydrogen atom at the α-position.
The present invention has been accomplished by knowing that an organic iridium complex having a membered ring type ligand is a triplet phosphorescent dye having excellent performance. That is, the present invention resides in an organic iridium complex represented by the following general formula (i) and an organic electroluminescence device using the same.

[0015]

[Chemical 9]

(Where m is the number of ligands L, 0, 1
Or 2. L represents an arbitrary bidentate ligand. Ring A represents a 5-membered aromatic heterocyclic group having at least one hetero atom and may have a substituent. Ring B represents a 5-membered aromatic heterocyclic group containing a nitrogen atom and may have a substituent. Further, the group contained in ring A and the group contained in ring B may be bonded to each other to form a condensed ring containing ring A and ring B.
In addition, arbitrary substituents shall be bonded to the carbon atom at the α-position of the heteroatoms contained in ring A and ring B. )

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The organic iridium complex according to the present invention will be described.
The organic iridium complex used in the present invention has a structure represented by the above general formula (i) and is characterized by having a ligand in which five-membered rings are connected to each other. It is preferably represented by the following general formula (ii) or (iii).

[0018]

[Chemical 10]

In the above general formula, X, Y ¹ , Y ² and Z are each independently a sulfur atom, an oxygen atom, or --NR--
(In the formula (ii), R represents R ¹⁰⁵ , and in the formula (iii), R represents R ^110. R represents a hydrogen atom or a substituent described later for R ¹⁰⁵ and R ¹¹⁰ ). L is any 2
Represents a bidentate ligand. m represents the number of ligands and is 0, 1, or 2. R ¹⁰¹ , R ¹⁰⁵ , R ¹⁰⁷ and R ¹¹⁰ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group or an aryloxycarbonyl group. , Alkoxy group, carboxyl group,
It represents a hydroxyl group, a mercapto group, an alkylthio group, an arylthio group, a sulfonyl group, a silyl group, a boryl group, a phosphino group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, all of which may have a substituent. Good.

R ^{102 to} R ¹⁰⁴ , R ¹⁰⁶ , R ¹⁰⁸ and R ¹⁰⁹
Are each independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, cyano group, amino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkoxy group, carboxyl group, hydroxyl group, mercapto group, alkylthio group. Group, arylthio group,
It represents a sulfonyl group, a silyl group, a boryl group, a good phosphino group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, all of which may have a substituent. In addition, R ¹⁰¹ and R ¹⁰² , R ¹⁰³ and R ¹⁰⁴ , R ¹⁰⁶ and R ¹⁰⁷ , or R ¹⁰⁸ and R ¹⁰⁹ may be bonded to each other to form a ring.

Specific examples of the respective substituents listed as R ^{101 to} R ¹¹⁰ in the above general formulas (ii) and (iii) include the following groups. Halogen atom; fluorine atom,
Chlorine atom, bromine atom or iodine atom, alkyl group; preferably a linear or branched alkyl group having 1 to 8 carbon atoms, for example, methyl group, ethyl group, n-propyl group,
Alkenyl groups such as 2-propyl group, n-butyl group, isobutyl group, tert-butyl group; preferably alkenyl groups having 2 to 8 carbon atoms, for example, alkynyl groups such as vinyl group, allyl group, 1-butenyl group; Has 2 to 8 carbon atoms
An aralkyl group such as an ethynyl group or a propargyl group, an aralkyl group such as an benzyl group, an amino group such as a benzyl group, preferably an alkylamino group having at least one alkyl group having 1 to 8 carbon atoms (eg, methylamino group, dimethylamino group). Group, diethylamino group, dibenzylamino group, etc.), arylamino group (eg, phenylamino group, diphenylamino group, ditolylamino group, etc.), heteroarylamino group (eg, pyridylamino group, thienylamino group). ,
Examples thereof include a dithienylamino group. ), An alkoxy group such as an acylamino group (eg, an acetylamino group, a benzoylamino group, etc.); preferably an alkoxy group having 1 to 8 carbon atoms (eg, a methoxy group, an ethoxy group, a butoxy group, etc.), An aryloxy group (having an aromatic hydrocarbon group or a heterocyclic group, and examples thereof include a phenyloxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a pyridyloxy group, a thienyloxy group, etc.) and the like. , An acyl group; preferably an acyl group having 1 to 8 carbon atoms, for example, a formyl group, an acetyl group, a benzoyl group, and the like, an alkoxycarbonyl group; preferably an alkoxylbonyl group having 2 to 13 carbon atoms, for example, methoxycarbonyl. Groups, ethoxycarbonyl groups, and other aryloxycarbonyl groups;
Preferred is an aryloxycarbonyl group having 5 to 13 carbon atoms, for example, a phenyloxycarbonyl group, a thienyloxycarbonyl group, a carboxyl group, a cyano group, a hydroxyl group, a mercapto group, an alkylthio group; preferably an alkylthio group having 1 to 8 carbon atoms. A group, for example, an arylthio group such as a methylthio group or an ethylthio group;
Preferred is an arylthio group having 6 to 20 carbon atoms, for example, a sulfonyl group such as a phenylthio group, a 1-naphthylthio group; a silyl group such as a mesyl group or a tosyl group; a boryl group such as a trimethylsilyl group or a triphenylsilyl group; A phosphino group such as a dimesitylboryl group; an aromatic hydrocarbon ring group or an aromatic heterocyclic group such as a diphenylphosphino group; preferably 5
Or a six-membered, monocyclic or two-condensed aromatic hydrocarbon ring or aromatic heterocycle, for example, a phenyl group, a naphthyl group, a thienyl group, a furyl group, a pyridyl group, etc., each of which is further substituted The substituent may be a halogen atom or an alkyl group having 1 to 10 carbon atoms.

The bidentate ligand L is not limited in its structure as long as it does not impair the characteristics of the compound of the present invention. Specific examples thereof include the bidentate ligands shown below.

[0023]

[Chemical 11]

Each of the above ligands is R ¹⁰² to
R ¹⁰⁴ , R ¹⁰⁶ , R ¹⁰⁸ and R ¹⁰⁹ may have a substituent such as the groups described above. In the compound of the present invention, the group bonded to the α-position carbon atom of the hetero atom in the aromatic hetero 5-membered ring in the ligand, that is, the general formula (i
In i), R ¹⁰² , R ¹⁰³ and R ¹⁰⁴ , the general formula (iii)
R ¹⁰⁶ , R ¹⁰⁸ and R ^{109 in} are all groups other than hydrogen atom. Preferably, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, an acyl group which may have a substituent, a carboxyl group, and an aromatic carbon which may have a substituent. It is a hydrogen ring group or an aromatic heterocyclic group, which may be linked to adjacent groups to form a ring.

The 5-membered ring containing a hetero atom has a high reactivity among other aromatic compounds and hetero rings, and particularly the α-position has a very high reaction activity. (For example, it exhibits reactivity such as electrophilic substitution reaction, protonation, and Diels-Alder reaction.) A compound having a ligand containing an unsubstituted 5-membered ring at the α-position was used as a material for an organic electroluminescence device. In this case, the stability of the device may be reduced, which may lead to a decrease in luminous efficiency and a shortened life.

Therefore, the organic iridium complex of the present invention is
In addition, when it is used as an organic electroluminescent device material, α
It is essential to introduce a substituent into the-position. General formula (i
R in i)¹⁰¹And R¹⁰⁵, And the general formula (iii)
R in^{1 07}And R¹¹⁰Are each hydrogen atom or
Is R¹⁰²~ R¹⁰⁴, R¹⁰⁶, R¹⁰⁸And R¹⁰⁹Listed as
And each of the groups mentioned above are mentioned as specific examples of each group.
You can Among them, hydrogen atom or R is preferable.¹⁰²~
R¹⁰⁴, R¹⁰⁶, R¹⁰⁸And R ¹⁰⁹As preferred above
Group, and more preferably a hydrogen atom or
A group in contact with each other is bonded to form a ring.

The organic iridium complex used in the present invention is 5
It is characterized by having a bidentate ligand in which member rings are connected to each other. Many of these compounds show an emission spectrum with a narrow half-value width in the emission spectrum in a solution at low temperature, and can be expected to improve color purity, high efficiency, and long device life. It is a thing. Representative examples of the compound of the present invention are shown below, but the compound of the present invention is not limited thereto.

[0028]

[Chemical 12]

[0029]

[Chemical 13]

[0030]

[Chemical 14]

[0031]

[Chemical 15]

The compound represented by the general formula (i) usually has a molecular weight of 2000 or less, preferably 1500 or less. The molecular weight of each ligand in the compound is 800 or less, and the molecular weight of the substituent is about 300 or less in total.

The organic electroluminescent device of the present invention is characterized in that an anode, a light emitting layer, and a cathode are sequentially laminated on a substrate, and the light emitting layer contains the compound represented by the general formula (i). And The organic iridium complex represented by the general formula (i) is preferably contained in the light emitting layer after being doped with a host compound having a hole injecting / transporting property or an electron injecting / transporting property.

In the light emitting layer of the organic electroluminescent element of the present invention, one kind of the organic iridium complex of the present invention may be contained alone, or two or more kinds thereof may be contained. Hereinafter, the host compound suitable for the present invention will be described. The host compound preferably has an excited triplet level in an energy state higher than the excited triplet level of the Ir complex represented by the general formula (i) contained in the light emitting layer. In addition, it gives a stable thin film shape, has a high glass transition temperature (Tg),
It is necessary that the compound be capable of efficiently transporting holes and / or electrons.

Further, it is required that the compound is electrochemically and chemically stable, and that the impurities that become traps and quench the luminescence are hard to be generated at the time of production or use. As a host compound satisfying these conditions,
Examples thereof include compounds represented by the following general formula (I) or (II), or compounds having a group represented by the following general formula (III).

[0036]

[Chemical 16]

(In the formula (I), the carbazolyl group and the phenylene group may have an arbitrary substituent. Z ¹ represents a direct bond or a divalent linking group.)

[0038]

[Chemical 17]

(In the formula (II), M is a group 1 or 2 of the periodic table,
It represents a metal selected from Group 3, 12 or 13 and n represents the valence of the metal. L represents an arbitrary substituent, j represents the number of the substituent L, and is 0 or 1. X
² represents a carbon atom or a nitrogen atom. Ring A represents a nitrogen-containing heterocycle and may have a substituent. Ring B represents an aromatic hydrocarbon ring or an aromatic heterocycle, and may have a substituent. )

[0040]

[Chemical 18]

In the formula (III), R ^{51 to} R ⁵⁴ each independently represent a hydrogen atom or any substituent, and R ⁵¹ and R ⁵² , R ⁵³ and R ⁵⁴ are bonded to each other to form a ring. X ³ represents an oxygen atom or a sulfur atom.) The compound having the N-phenylcarbazole skeleton represented by the general formula (I) is preferably a compound represented by the following general formula (I-1). Is mentioned.

[0042]

[Chemical 19]

(In the formula (I-1), R ^{1 to} R ¹⁶ are each independently a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, Represents a carboxyl group, an alkoxy group, an alkylamino group, an aralkylamino group, a haloalkyl group, a hydroxyl group, an aryloxy group, an aromatic hydrocarbon ring group which may have a substituent or an aromatic heterocyclic group, and R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ , R ⁷ and R
⁸ , R ⁹ and R ¹⁰ , R ¹¹ and R ¹² , R ¹³ and R ¹⁴ , R ¹⁵ and R ¹⁶
May be bonded to each other to form a ring. Z ¹ represents a direct bond or a divalent linking group. As R ^{1 to} R ¹⁶ in the formula (I-1), specifically, a hydrogen atom; a halogen atom such as a chlorine atom or a fluorine atom; an alkyl group having 1 to 6 carbon atoms such as a methyl group or an ethyl group; benzyl Aralkyl groups such as groups; alkenyl groups having 2 to 6 carbon atoms such as vinyl groups;
Cyano group; amino group; acyl group; alkoxycarbonyl group having 2 to 6 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group; carboxyl group; alkoxy group having 1 to 6 carbon atoms such as methoxy group and ethoxy group; diethylamino group, Alkylamino groups such as diisopropylamino groups; aralkylamino groups such as dibenzylamino groups and diphenethylamino groups; haloalkyl groups such as trifluoromethyl groups; hydroxyl groups; aryloxy groups such as phenoxy groups and benzyloxy groups; Examples thereof include an aromatic hydrocarbon ring group such as a phenyl group and a naphthyl group which may have; an aromatic heterocyclic group such as a thienyl group and a pyridyl group which may have a substituent.

The substituents that the aromatic hydrocarbon ring group and aromatic heterocyclic group may have include halogen atoms such as fluorine atom; alkyl groups having 1 to 6 carbon atoms such as methyl group and ethyl group; vinyl group. An alkenyl group having 2 to 6 carbon atoms such as; a carbon number 2 such as a methoxycarbonyl group and an ethoxycarbonyl group
~ 6 alkoxycarbonyl group; C1-6 alkoxy group such as methoxy group, ethoxy group; aryloxy group such as phenoxy group, benzyloxy group; alkylamino group such as dimethylamino group, diethylamino group; acetyl group, etc. An acyl group; a haloalkyl group such as a trifluoromethyl group; and a cyano group.

The alkyl chain portion contained in each of the above substituents may be linear or branched. The same applies to the following examples of substituents. Also,
R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ , R ⁷ and R ⁸ , R
⁹ and R ¹⁰ , R ¹¹ and R ¹² , R ¹³ and R ¹⁴ , and R ¹⁵ and R ¹⁶ are bonded to each other by adjacent substituents to form a 5- to 7-membered ring such as a benzene ring and a cyclohexane ring. Is also good.

Particularly preferred as R ¹ to R ¹⁶ are
It is a hydrogen atom, an alkyl group, or a cyano group. Z ¹ in the general formula (I) or (I-1) is preferably a direct bond, an oxygen atom, a sulfur atom, a linking group shown below,

[0047]

[Chemical 20]

Examples thereof include a divalent aromatic hydrocarbon ring group or an aromatic heterocyclic group which may have a substituent, or one of the following linking groups.

[0049]

[Chemical 21]

(Each of the benzene ring moieties in the above structure may have an arbitrary substituent, and Ar ^{1 to} Ar ⁶ may have an aromatic hydrocarbon ring group or aromatic group which may have a substituent. Group heterocyclic groups or groups represented by general formula (I-2) shown below can be given.

[0051]

[Chemical formula 22]

The carbazolyl group and phenylene group in the formula (I-2) may have any substituent. ) Among the preferable linking groups for Z ¹ in formula (I) or (I-1), the aromatic hydrocarbon ring group is a 5- or 6-membered ring such as a phenylene group, a naphthylene group, an anthranyl group or a naphthacene group. A monocycle or a condensed ring of 2 to 4,
As the aromatic heterocyclic group, a divalent thiophene ring residue, a furan ring residue, a pyridine ring residue, a pyrimidine ring residue, a quinoline ring residue or the like, a 5- or 6-membered monocyclic ring or 2-3 Examples include condensed rings.

These aromatic hydrocarbon ring groups and aromatic heterocyclic groups include an alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group, a halogen atom such as a fluorine atom and an α-group such as a trifluoromethyl group. It may have a substituent such as a haloalkyl group. Further, as Ar ^{1 to} Ar ⁶ , 5 to 6 such as phenyl group, naphthyl group, anthranyl group and naphthacenyl group are used.
5- to 6-membered monocyclic ring or 2-membered ring aromatic hydrocarbon ring group which is a monocyclic ring or a 2- to 4-condensed ring, or a thienyl group, a furyl group, a pyridyl group, a pyrimidinyl group, a quinolyl group or the like.
˜3 condensed ring aromatic heterocyclic groups. These aromatic hydrocarbon ring groups and aromatic heterocyclic groups have a substituent such as an alkyl group such as a methyl group and an ethyl group, a halogen atom such as a fluorine atom, and an α-haloalkyl group such as a trifluoromethyl group. May be.

The structure represented by the above formula (I-2) is preferably represented by the following formula (I-3).

[0055]

[Chemical formula 23]

(In the formula (I-3), R¹⁷~ R^{twenty four}Each is independent
, Hydrogen atom, halogen atom, alkyl group, aralkyl
Group, alkenyl group, cyano group, may have a substituent
Amino group, acyl group, alkoxycarbonyl group, calcium
Voxyl group, alkoxy group, haloalkyl group, hydroxyl group,
Aryloxy group, aromatic carbon which may have a substituent
Represents a hydrogenated ring group or an aromatic heterocyclic group, R¹⁷When
R¹⁸, R¹⁹And R²⁰, R^{twenty one}And R ^{twenty two}, R^{twenty three}And R^{twenty four}Are each
They may be bonded to each other to form a ring. ) In the above formula (I-3), R¹⁷~ R^{twenty four}As concrete
Include hydrogen atom; halogen atom; methyl group, ethyl group, etc.
An alkyl group having 1 to 6 carbon atoms; aralkyl such as benzyl group
Group; alkenyl group having 2 to 6 carbon atoms such as vinyl group; sia
Group; amino group; diethylamino group, diisopropyl group
Alkylamino group such as mino group; dibenzylamino group, di
Aralkylamino group such as phenethylamino group; Acyl
Group; methoxycarbonyl group, ethoxycarbonyl group, etc.
C2-C6 alkoxycarbonyl group; carboxyl
Group: Alcohol having 1 to 6 carbon atoms such as methoxy group and ethoxy group
Xy group; haloalkyl group such as trifluoromethyl group; water
Acid group; aryl such as phenoxy group and benzyloxy group
Oxy group; phenyl group which may have a substituent, naphth
Aromatic hydrocarbon ring group such as chill group; even if it has a substituent
Aromatic heterocyclic groups such as good thienyl group and pyridyl group are listed.
To be

The substituents that the aromatic hydrocarbon ring group and aromatic heterocyclic group may have include halogen atoms such as fluorine atom; alkyl groups having 1 to 6 carbon atoms such as methyl group and ethyl group; vinyl group. An alkenyl group having 2 to 6 carbon atoms such as; a carbon number 2 such as a methoxycarbonyl group and an ethoxycarbonyl group
~ 6 alkoxycarbonyl group; methoxy group, ethoxy group, and other C1-6 alkoxy groups; phenoxy group, benzyloxy group, and other aryloxy groups; dimethylamino group, diethylamino group, and other dialkylamino groups, acetyl group, etc. An acyl group; a haloalkyl group such as a trifluoromethyl group; and a cyano group.

R ¹⁷ and R ¹⁸ , R ¹⁹ and R ²⁰ , R ²¹ and R ²² , and R ²³ and R ²⁴ are bonded to each other by adjacent substituents, and are a 5- to 7-membered ring such as a benzene ring or a cyclohexane ring. May be formed. Specific preferred examples of the compound represented by the general formula (I) are shown below, but the invention is not limited thereto.

[0059]

[Chemical formula 24]

[0060]

[Chemical 25]

[0061]

[Chemical formula 26]

[0062]

[Chemical 27]

[0063]

[Chemical 28]

In the organic electroluminescent device of the present invention, the organometallic complex compound represented by the general formula (II) may be used as the host compound in the light emitting layer. The general formula (I
As the host compound represented by the formula (I), in particular, an organometallic complex represented by the following general formula (II-1), a mixed ligand complex represented by the following general formula (II-2), or the following general formula (II The binuclear metal complex represented by -3) is preferable.

[0065]

[Chemical 29]

(In the formula (II-1), M ¹ represents a monovalent to trivalent metal, and n, X ² , ring A and ring B are represented by the general formula (I
Synonymous with I). )

[0067]

[Chemical 30]

(In the formula (II-2), M ² represents a trivalent metal, and X ² , ring A and ring B have the same meanings as in the general formula (II). L ¹ represents the following general formula (II). -2a), (II-2
b) or (II-2c). )

[0069]

[Chemical 31]

((II-2a), (II-2b), (II-2
c) In the formula, Ar ^{11 to} Ar ¹⁵ represent an aromatic hydrocarbon ring group which may have a substituent or an aromatic heterocyclic group which may have a substituent, and Z ² represents silicon or germanium. Represents )

[0071]

[Chemical 32]

[0072] ((II-3) wherein, M ³ and M ^{3 'represents} a trivalent metal, X ^2, ring A and ring B have the same meanings as in the general formula (II), X ^2' is X ² and ring A ′ are ring A,
Ring B'is synonymous with ring B, respectively. ) In addition, a plurality of the following structural moieties contained in one molecule of the compounds represented by the general formulas (II) and (II-1) to (II-3).

[0073]

[Chemical 33]

(In the general formula (II-3), the following structural moiety is present in twos in one compound.

[0075]

[Chemical 34]

), That is, ring A, ring B, and X ² (formula (II
In the case of -3), ring A, ring A ′, ring B, ring B ′, X ² and X ^{2 ′} ) may be the same or different. From the viewpoint of easy synthesis, all are preferably the same. Similarly, M ³ and M ^{3 ′} in the compound represented by the general formula (II-3) may be the same or different, and are preferably the same from the viewpoint of easy synthesis.

The above general formulas (II) and (II-1) to (II
The ring A, ring A ′, ring B, and ring B ′ of the compound represented by -3) are preferably selected from the following. [Ring A and Ring A ′] A 5-membered or 6-membered nitrogen-containing aromatic heterocyclic ring which may have a substituent, and a 5- or 6-membered aromatic hydrocarbon ring or aromatic ring in the ring. Group heterocycle is 1
Alternatively, two of them may be condensed to form a condensed ring. [Ring B and Ring B ′] A 6-membered aromatic hydrocarbon ring or aromatic heterocycle which may have a substituent, and a 5- or 6-membered aromatic hydrocarbon ring or aromatic ring in the ring. One or two group heterocycles may be condensed to form a condensed ring.

The above general formulas (II) and (II-1) to (II
As the ring A, the ring A ′, the ring B, and the ring B ′ of the compound represented by -3), each is more preferably a single ring, and among them, a ring selected from the following is preferable. [Ring A and Ring A ′] Each may have a diazole ring, a thiazole ring, an oxazole ring, a thiadiazole ring, an oxadiazole ring, a triazole ring, a pyridine ring, a diazine ring, a triazine ring [ring B And ring B ′] each of which may have a substituent, a benzene ring, a pyridine ring, a diazine ring, a triazine ring, and a compound represented by the general formula (II) and (II-1) to (II-3). Most preferably, ring A, ring A ′, ring B, and ring B ′ are each selected from the following structural formulas.

[0079]

[Chemical 35]

(In the formula, R ^{31 to} R ³⁷ are each independently a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, a carboxyl group, an alkoxy group. Represents an alkylamino group, an aralkylamino group, a haloalkyl group, a hydroxyl group, an aryloxy group, an aromatic hydrocarbon ring group which may have a substituent or an aromatic heterocyclic group which may have a substituent. , R ³¹ and R ³² , R ³¹ and R ³³ , R ³⁴ and R
³⁵ , R ³⁵ and R ³⁶ , and R ³⁶ and R ³⁷ may be bonded to each other to form a ring. )

[0081]

[Chemical 36]

(In the formula, R ^{38 to} R ⁴¹ are each independently a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, a carboxyl group, an alkoxy group. Represents an alkylamino group, an aralkylamino group, a haloalkyl group, a hydroxyl group, an aryloxy group, an aromatic hydrocarbon ring group which may have a substituent or an aromatic heterocyclic group which may have a substituent. , R ³⁸ and R ³⁹ , R ³⁹ and R ⁴⁰ , R ⁴⁰ and R
⁴¹ may combine with each other to form a ring. ) The two bonds in the structure of [ring B and ring B ′] satisfy the definitions of the structure of ring B and ring B ′ in the formulas (II) and (II-1) to (II-3). As long as it is an oxygen atom, or atoms X ² and X ^{2 ′} in ring A and ring A ′.
Of these, any may be bonded to any.

As R ^{31 to} R ⁴¹ , specifically, a hydrogen atom;
Halogen atom; alkyl group having 1 to 6 carbon atoms such as methyl group and ethyl group; aralkyl group such as benzyl group; alkenyl group having 2 to 6 carbon atoms such as vinyl group; cyano group; amino group;
Acyl group; carboxyl group; alkoxy group having 1 to 6 carbon atoms such as methoxy group and ethoxy group; alkoxycarbonyl group having 2 to 6 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group; aryl such as phenoxy group and benzyloxy group Oxy group; dialkylamino group such as diethylamino group, diisopropylamino group; dibenzylamino group; diaralkylamino group such as diphenethylamino group; α-haloalkyl group such as trifluoromethyl group; hydroxyl group; Aromatic hydrocarbon ring groups such as phenyl group and naphthyl group; and aromatic heterocyclic groups such as thienyl group and pyridyl group which may have a substituent.

The substituents that the aromatic hydrocarbon ring group and aromatic heterocyclic group may have include halogen atoms such as fluorine atom; alkyl groups having 1 to 6 carbon atoms such as methyl group and ethyl group; vinyl group. An alkenyl group having 2 to 6 carbon atoms such as; a carbon number 2 such as a methoxycarbonyl group and an ethoxycarbonyl group
~ 6 alkoxycarbonyl group; C1-6 alkoxy group such as methoxy group, ethoxy group; aryloxy group such as phenoxy group, benzyloxy group; dialkylamino group such as dimethylamino group, diethylamino group; acetyl group, etc. An acyl group; a haloalkyl group such as a trifluoromethyl group; and a cyano group.

Note that R³¹And R³², R³¹And R³³, R³⁴And R
³⁵, R³⁵And R³⁶, R³⁶And R³⁷, R³⁸And R³⁹, R³⁹When
R⁴⁰, R⁴⁰And R⁴¹Are bound to each other by adjacent groups
The ring to be formed is a benzene ring or cyclohexa
Ring and the like. R³¹~ R ⁴¹As preferably,
Hydrogen atom, halogen atom, alkyl group, alkoxy group,
Aromatic group optionally having haloalkyl group or substituent
Hydrocarbon groups, or bonded with adjacent groups
Form a ring.

General formulas (II) and (II-1) to (II-
3) Metal compound M (M ¹, M², M³And
And M^{3 '}) Is the periodic table 1 group, 2 group, 3 group, 12 group, 13
The metal selected from the group is not particularly limited, but is preferably
Zinc, aluminum, gallium, beryllium,
And magnesium. The general formula (II) and
And preferred compounds represented by (II-1) to (II-3)
Specific examples are shown below, but the present invention is not limited to these.
Yes.

[0087]

[Chemical 37]

[0088]

[Chemical 38]

[0089]

[Chemical Formula 39]

[0090]

[Chemical 40]

[0091]

[Chemical 41]

[0092]

[Chemical 42]

In the organic electroluminescent element of the present invention, a compound having a group represented by the above general formula (III) may be used as a host compound in the light emitting layer. In the general formula (III), examples of the ring formed by combining R ⁵¹ and R ⁵² and R ⁵³ and R ⁵⁴ include a benzene ring and a cyclohexane ring. In the general formula (III),
R ^{51 to} R ⁵⁴ are specifically a hydrogen atom; a halogen atom;
An alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group; an aralkyl group such as a benzyl group; an alkenyl group such as a vinyl group; a cyano group; an amino group; an acyl group; a methoxy group, an ethoxy group and the like 6 alkoxy group; alkoxycarbonyl group having 1 to 6 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group; aryloxy group such as phenoxy group and benzyloxy group; dialkylamino group such as diethylamino group and diisopropylamino group; dibenzyl Diaralkylamino group such as amino group and diphenethylamino group; α-haloalkyl group such as trifluoromethyl group; hydroxyl group; aromatic hydrocarbon ring group such as phenyl group and naphthyl group which may have a substituent; A thienyl group which may have a substituent, an aromatic heterocyclic group such as a pyridyl group, and the like Is a halogen atom such as a fluorine atom; an alkyl group having 1 to 6 carbon atoms such as methyl group and ethyl group; an alkenyl group such as vinyl group; an alkoxycarbonyl group having 1 to 6 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group. A carbon number of 1 such as a methoxy group and an ethoxy group
An alkoxy group of 6 to 6; an aryloxy group such as a phenoxy group and a benzyloxy group; a dialkylamino group such as a dimethylamino group and a diethylamino group; an acyl group such as an acetyl group; a haloalkyl group such as a trifluoromethyl group; and a cyano group. To be

Specific preferred examples of the group represented by the general formula (III) are shown below, but the invention is not limited thereto.

[0095]

[Chemical 43]

The compound having a group represented by the general formula (III) may be a low molecule or a polymer. In the case of a polymer, it may be contained in the main chain,
It may be contained as a side chain. This compound is preferably a low molecular weight compound having a molecular weight of about 400 to 1200, and the compound having a group represented by the general formula (III) is
The total number of rings as the whole compound is preferably 6 to 20, and more preferably 7 to 18. Further, the compound having a group represented by the general formula (III) is preferably a compound having 2-3 units represented by the general formula (III) in the molecule.

Among them, the group represented by the general formula (III) is
The above-mentioned (S-1) or (S-2) is particularly preferable. The compound having a group represented by the general formula (III) is
A compound represented by the following general formula (III-1) or (III-2) is preferable.

[0098]

[Chemical 44]

(In the formula, R ^{55 to} R ⁶² are each independently a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, an allyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, a carboxyl group. , An alkoxy group, an alkylamino group, an α-haloalkyl group, a hydroxyl group,
And R ⁵⁵ and R ⁵⁶ , R ⁵⁷ and R ⁵⁸ , and R ⁵⁹ , which represent an aromatic hydrocarbon ring group or an aromatic heterocyclic group which may have a substituent.
And R ⁶⁰ , and R ⁶¹ and R ⁶² may be bonded to each other to form a ring. X ⁴ and X ⁵ each independently represent an oxygen atom or a sulfur atom, and Q ¹ represents a divalent linking group consisting of an aromatic hydrocarbon ring group or an aromatic heterocyclic group which may have a substituent. Show. )

[0100]

[Chemical formula 45]

(In the formula, R⁶³~ R⁷⁴Are independently hydrogen
Child, halogen atom, alkyl group, aralkyl group, alkene
Nyl group, allyl group, cyano group, amino group, acyl group,
Lucoxycarbonyl group, carboxyl group, alkoxy
Group, alkylamino group, α-haloalkyl group, hydroxyl group,
Aromatic hydrocarbon ring group or aromatic group which may have a substituent
Represents an aromatic heterocyclic group, R⁶³And R⁶⁴, R⁶⁵And R⁶⁶, R⁶⁷
And R⁶⁸, R⁶⁹And R⁷⁰, R⁷¹And R⁷², R⁷³And R⁷⁴Is that
And they may be bonded to each other to form a ring. X⁶~ X⁸Are each
Independently represent an oxygen atom or a sulfur atom, and Q²Is a substituent
An aromatic hydrocarbon ring group or aromatic compound which may have
A trivalent linking group consisting of an elementary ring group is shown. ) In the general formula (III-1), R⁵⁵~ R⁶²Each is German
By the way, hydrogen atom; halogen atom; methyl group, ethyl group, etc.
An alkyl group having 1 to 6 carbon atoms; aralkyl such as benzyl group
Group; alkenyl group such as vinyl group; cyano group; amino
Group; acyl group; methoxy group, ethoxy group, etc., having 1 to 1 carbon atoms
6 alkoxy group; methoxycarbonyl group, ethoxyca
Alkoxycarbonyl having 1 to 6 carbon atoms such as rubonyl group
Group; aryloxy groups such as phenoxy group and benzyloxy group
Xy group; diethylamino group, diisopropylamino group, etc.
Dialkylamino group; dibenzylamino group, diphenene
Diaralkylamino group such as tylamino group; trifluor
Α-haloalkyl group such as dimethyl group; hydroxyl group;
Aromatic carbon such as phenyl and naphthyl groups that may be present
Hydrogenated ring group; optionally substituted thienyl group, phenyl group
Represents an aromatic heterocyclic group such as a lysyl group and has the above-mentioned substituent
Are halogen atoms such as fluorine atom; methyl group, ethyl
An alkyl group having 1 to 6 carbon atoms such as a group; an alke such as a vinyl group
Nyl group; methoxycarbonyl group, ethoxycarbonyl group
An alkoxycarbonyl group having 1 to 6 carbon atoms such as; methoxy
Group, alkoxy group having 1 to 6 carbon atoms such as ethoxy group;
Aryloxy groups such as noxy group and benzyloxy group;
Dialkyl groups such as dimethylamino group and diethylamino group
Amino group, acyl group such as acetyl group, trifluoromethyl
A haloalkyl group such as a group and a cyano group are shown. R⁵⁵And R⁵⁶,
R⁵⁷And R⁵⁸, R⁵⁹And R⁶⁰, R ⁶¹And R⁶²Are combined respectively
To form a benzene ring, cyclohexane ring, etc.
Yes. X^Four~ X^FiveEach independently represents an oxygen atom or a sulfur atom.
Show. Q¹Is an aromatic aromatic carbon which may have a substituent
Divalent linking group consisting of hydrogenated ring group or aromatic heterocyclic group
Represents a halogen atom such as a fluorine atom.
Atom: alkyl having 1 to 6 carbon atoms such as methyl group and ethyl group
Group; alkenyl group having 2 to 6 carbon atoms such as vinyl group; metoki
2 to 2 carbon atoms such as cycarbonyl and ethoxycarbonyl groups
6 alkoxycarbonyl group; methoxy group, ethoxy group
An alkoxy group having 1 to 6 carbon atoms such as phenoxy group, benzene
Aryloxy groups such as diloxy groups; dimethylamino
Group, dialkylamino group such as diethylamino group, acetyl
Group such as acyl group and haloalkyl group such as trifluoromethyl group
Examples thereof include a kill group and a cyano group. Linking group Q¹Preferred
A new example is shown below.

[0102]

[Chemical formula 46]

Of these, the linking group Q ¹ is (A-
2), (A-6), (A-8), (A-10) or (A-12) is preferable. Then, a compound having these linking groups Q ¹ and having (S-1) or (S-2) as a ring structure is most preferable. The general formula (III
Preferred specific examples of the compound represented by -1) are shown in Tables 1 and 2.
However, the present invention is not limited to these.

[0104]

[Table 1]

[0105]

[Table 2]

In the general formula (III-2), R⁶³~
R⁷⁴Are each independently a hydrogen atom; a halogen atom; methyl
Groups, alkyl groups having 1 to 6 carbon atoms such as ethyl group; benzyl
Aralkyl groups such as groups; alkenyl groups such as vinyl groups; sia
Group; amino group; acyl group; methoxy group, ethoxy group, etc.
An alkoxy group having 1 to 6 carbon atoms; methoxycarbonyl
Group, ethoxycarbonyl group, etc. Alkoxy having 1 to 6 carbon atoms
Sicarbonyl group; phenoxy group, benzyloxy group, etc.
Aryloxy group; diethylamino group, diisopropylpropionate
Dialkylamino groups such as ruamino group; dibenzylamino
Group, diphenethylamino group and other diaralkylamino
Group; α-haloalkyl group such as trifluoromethyl group; water
Acid group; phenyl group which may have a substituent, naphthyl
Aromatic hydrocarbon ring groups such as groups; may have a substituent
Represents an aromatic heterocyclic group such as a thienyl group or a pyridyl group,
As the substituent, a halogen atom such as a fluorine atom;
C1-C6 alkyl groups such as chill and ethyl; vinyl
Alkenyl group such as methoxy group, methoxycarbonyl group, etoki
Alkoxycarboni having 1 to 6 carbon atoms such as carbonyl group
Group; methoxy group, ethoxy group, etc., having 1 to 6 carbon atoms
Coxy group; Ant such as phenoxy group and benzyloxy group
Group; dimethylamino group, diethylamino group, etc.
Dialkylamino group, acyl group such as acetyl group, trialkyl
Indicates a haloalkyl group such as a fluoromethyl group or a cyano group.
You R⁶³And R⁶⁴, R⁶⁵And R⁶⁶, R⁶⁷And R⁶⁸, R ⁶⁹When
R⁷⁰, R⁷¹And R⁷², R⁷³And R⁷⁴Are connected to each other
Even if it forms a benzene ring, cyclohexane ring, etc.
good. X⁶~ X⁸Are each independently an oxygen atom or a sulfur atom
Indicates. Q²Is an aromatic aromatic group which may have a substituent
Trivalent link consisting of hydrocarbon ring group or aromatic heterocyclic group
Group, and the substituent is a halogen atom such as a fluorine atom.
Carbon atom; alkyl group having 1 to 6 carbon atoms such as methyl group and ethyl group
Group; alkenyl group having 2 to 6 carbon atoms such as vinyl group; meth
2 carbon atoms such as xycarbonyl group and ethoxycarbonyl group
~ 6 alkoxycarbonyl group; methoxy group, ethoxy
C1-C6 alkoxy groups such as groups; phenoxy groups,
Aryloxy groups such as benzyloxy group; dimethylamino
Group, dialkylamino group such as diethylamino group, acetyl
Group such as acyl group and haloalkyl group such as trifluoromethyl group
Examples thereof include a kill group and a cyano group. Linking group Q²Preferred
A new example is shown below.

[0107]

[Chemical 47]

Among these, the linking group Q ² is (B-
1), (B-2) or (B-7) are preferred. Most preferably, it has these linking groups and has (S-
1) or (S-2). Specific preferred examples of the compound represented by the general formula (III-2) are shown in Tables 3 and 4, but are not limited thereto.

[0109]

[Table 3]

[0110]

[Table 4]

The compound represented by the general formula (I), the compound represented by the general formula (II), and the general formula (II
The compound having a group represented by I) is 1 in each of the light emitting layers.
Only one species may be contained, or two or more species may be contained. Moreover, you may use together the compound represented by a different general formula. As the host compound, the above-mentioned general formula (I) is used.
In addition to (III), the following compounds may be used.

[0112]

[Chemical 48]

[0113]

[Chemical 49]

(In the formula (4), the ligand 8-hydroxyquinoline structure has a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, or a methyl group,
It may be substituted with a linear or branched alkyl group having 1 to 5 carbon atoms such as an ethyl group and a t-butyl group. The three ligands in one compound may have the same structure or different structures. As described above, as the host compound, a plurality of compounds that can be represented by the same general formula may be used in combination, or two or more compounds that cannot be represented by the same general formula may be used in combination.

In the organic electroluminescent device of the present invention, the compound represented by the general formula (I) or the compound represented by the general formula (IV) is particularly preferable as the host compound of the light emitting layer. Next, the structure of the organic electroluminescent element of the present invention will be described with reference to the drawings.
The structure of the organic electroluminescent element of the present invention is not limited to that shown in the drawings.

FIGS. 1 to 3 are sectional views schematically showing an embodiment of the organic electroluminescent device of the present invention, in which 1 is a substrate, 2 is an anode, 3 is an anode buffer layer, 4 is a hole transport layer, Reference numeral 5 is a light emitting layer, 6 is a hole blocking layer, 7 is an electron transport layer, and 8 is a cathode. Hereinafter, the element shown in FIG. 1 will be mainly described. The substrate 1 serves as a support for the organic electroluminescent device, and a plate of quartz or glass, a metal plate or metal foil, a plastic film or sheet, or the like is used. In particular, a glass plate and a transparent synthetic resin plate such as polyester, polymethacrylate, polycarbonate, and polysulfone are preferable. When using a synthetic resin substrate, it is necessary to pay attention to the gas barrier property. If the gas barrier property of the substrate is too small, the organic electroluminescent element may deteriorate due to the outside air passing through the substrate, which is not preferable. Therefore, a method of providing a dense silicon oxide film or the like on at least one surface of the synthetic resin substrate to secure the gas barrier property is also a preferable method.

An anode 2 is provided on the substrate 1. Anode 2
Plays a role of injecting holes into the hole transport layer 4. This anode 2 is usually a metal such as aluminum, gold, silver, nickel, palladium, platinum, indium and / or
Alternatively, a metal oxide such as tin oxide, a metal halide such as copper iodide, carbon black, or a conductive polymer such as poly (3-methylthiophene), polypyrrole, or polyaniline is used. The anode 2 is usually formed by a sputtering method, a vacuum vapor deposition method, or the like. When fine particles of metal such as silver, fine particles of copper iodide, carbon black, fine particles of conductive metal oxide, fine particles of conductive polymer, etc. are used, they are dispersed in an appropriate binder resin solution and then the substrate 1 The anode 2 can also be formed by applying the composition onto the anode 2. Further, in the case of a conductive polymer, a thin film can be formed directly on the substrate 1 by electrolytic polymerization, or a conductive polymer can be applied on the substrate 1 to form the anode 2 (Appl. Phys. Lett. ． 、 60
Vol. 2711, 1992).

The anode 2 is composed of layers made of different materials.
It may have a laminated structure formed by laminating. The thickness of the anode 2 depends on the required transparency. When transparency is required, the visible light transmittance is usually 60% or more,
It is preferable to set it to 80% or more, and in this case,
The thickness is usually 5 to 1000 nm, preferably 10 to 500 nm. When it is opaque, the thickness of the anode 2 may be about the same as that of the substrate 1. Further, it is also possible to stack different conductive materials on the anode 2.

A hole transport layer 4 is provided on the anode 2. The conditions required for the material of the hole transport layer 4 include a material having a high hole injection efficiency from the anode 2 and capable of efficiently transporting the injected holes. For that purpose, the ionization potential is low, the transparency to visible light is high, the hole mobility is high, the stability is excellent, and impurities that serve as traps are less likely to be generated during manufacturing or use. Required.
Further, it is required that the light emitted from the light emitting layer 5 is not quenched because it is in contact with the light emitting layer 5 or that the efficiency is not lowered by forming an exciplex with the light emitting layer 5. In addition to the above general requirements, when considering application for in-vehicle display, since the element is required to have further heat resistance, a material having a value of 75 ° C or higher as Tg is desirable, and a value of 85 ° C or higher is particularly desirable. Materials having are preferred.

Examples of such a hole transport material include, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino].
Contains two or more tertiary amines represented by biphenyl 2
Aromatic diamine in which one or more fused aromatic rings are substituted with nitrogen atoms (Japanese Patent Laid-Open No. 5-234681), 4,4 ', 4 "-tris (1-
Aromatic amine compounds with a starburst structure such as naphthylphenylamino) triphenylamine (J. Lumi
n., 72-74, p. 985, 1997), an aromatic amine compound consisting of a tetramer of triphenylamine (Chem. Commun., 2
175, 1996), 2,2 ', 7,7'-tetrakis- (diphenylamino) -9,9'-spirobifluorene and other spiro compounds (S
ynth. Metals, 91, 209 pages, 1997) and the like. These compounds may be used alone, or may be mixed and used if necessary.

In addition to the above compounds, as a material for the hole transport layer 4, polyvinylcarbazole, polyvinyltriphenylamine (JP-A-7-53953), and polyarylene ether sulfone containing tetraphenylbenzidine (Polym. Adv. Tech., Vol. 7, p. 33, 1996) and the like. When the hole transport layer 4 is formed by a coating method, an additive such as a binder resin or a coatability improving agent that does not become a hole trap is added to one or more hole transport materials, if necessary. A coating solution is prepared by dissolving, and the positive electrode 2 is coated by a method such as a spin coating method and dried to form the hole transport layer 4. Examples of the binder resin include polycarbonate, polyarylate, polyester and the like. If the binder resin is added in a large amount, it lowers the hole mobility, so a smaller amount is desirable,
Usually, the content in the hole transport layer 4 is preferably 50% by weight or less.

When the hole transport layer 4 is formed by the vacuum evaporation method, the hole transport material is put in a crucible installed in a vacuum container, and the inside of the vacuum container is adjusted to about 10 ⁻⁴ Pa by an appropriate vacuum pump. After evacuation to, the crucible is heated to evaporate the hole transport material and form the hole transport layer 4 on the substrate 1 on which the anode 2 is formed, facing the crucible. Hole transport layer 4
The film thickness of is usually 5 to 300 nm, preferably 10 to 100 nm. In order to uniformly form such a thin film, the vacuum evaporation method is often used.

The light emitting layer 5 is provided on the hole transport layer 4. The light emitting layer 5 contains at least the compound represented by the general formula (i) (organic iridium complex of the present invention), and usually further contains the above-mentioned various host compounds. The light emitting layer 5 is composed of holes injected from the anode 2 and moving in the hole transport layer 4 and electrons injected from the cathode 8 and moving in the hole blocking layer 6 between the electrodes to which an electric field is applied. Excited by recombination, it emits strong light. The maximum emission wavelength in the emission spectrum is derived from the organic iridium complex of the present invention. Use of the organic iridium complex of the present invention is particularly preferable for obtaining a device having an emission peak at a relatively long wavelength, particularly at a wavelength of 560 nm or more.

The light emitting layer 5 may contain components other than the organic iridium complex of the present invention and the host compound as long as the performance of the present invention is not impaired. For example, in the light emitting layer, in addition to (1) the host compound and (2) the organic iridium complex of the present invention, (3) phosphorescence is exhibited at room temperature,
A compound whose maximum emission wavelength is shorter than the maximum emission wavelength of (2) may be contained. This is because when the compound of the above (3) is used in combination, it plays the role of a sensitizer and the emission of the organic iridium complex of the present invention is enhanced. The above (3) may be selected from compounds represented by the general formula (i) of the present invention, and known phosphorescent compounds described in various documents and patents cited in the present specification. You can choose from the following. The structure is not limited as long as the condition (3) above is satisfied. The content of the organic iridium complex of the present invention represented by the general formula (i), which exhibits phosphorescence, is preferably in the range of 0.1 to 30% by weight based on the entire light emitting layer. If the content of the compound is less than 0.1% by weight, it may not be possible to sufficiently contribute to the improvement of the luminous efficiency of the device, and if it exceeds 30% by weight, concentration quenching may occur and the luminous efficiency may decrease. There is.

The compound of the present invention represented by the general formula (i) may be evenly distributed in the light emitting layer, or may be unevenly distributed in the film thickness direction. Light emitting layer 5
Has a thickness of usually 10 to 200 nm, preferably 20 to 1
00 nm. A thin film is formed in the same manner as the hole transport layer 4. The hole blocking layer 6 is laminated on the light emitting layer 5 so as to be in contact with the interface of the light emitting layer 5 on the cathode side, and blocks the holes moving from the hole transport layer 4 from reaching the cathode 8. It is formed of a compound that plays a role and can efficiently transport electrons injected from the cathode 8 toward the light emitting layer 5. The physical properties required for the material forming the hole blocking layer 6 are:
High electron mobility and low hole mobility are required. The hole blocking layer 6 has a function of confining holes and electrons in the light emitting layer 5 to improve light emission efficiency.

As the hole blocking material satisfying such conditions, a mixed ligand complex represented by the following general formula (VI) is preferable.

[0127]

[Chemical 50]

In the formula (VI), R ^{201 to} R ²⁰⁶ represent a hydrogen atom or any substituent, and Q ³ represents a metal atom selected from aluminum, gallium and indium.
³ is a general formula (VI-1), (VI-2), (VI-
It is represented by any of 3).

[0129]

[Chemical 51]

(In the formula, Ar ^{21 to} Ar ²⁵ represent an aromatic hydrocarbon ring group which may have a substituent or an aromatic heterocyclic group which may have a substituent, and Y ⁴ silicon Or germanium))) In the general formula (VI), R ^{201 to} R ²⁰⁶ each independently represent a hydrogen atom or an arbitrary substituent, but preferably a hydrogen atom; a halogen atom such as chlorine or bromine; a methyl group. , An alkyl group having 1 to 6 carbon atoms such as ethyl group; an aralkyl group such as benzyl group; an alkenyl group having 2 to 6 carbon atoms such as vinyl group;
Cyano group; amino group; acyl group; alkoxy group having 1 to 6 carbon atoms such as methoxy group and ethoxy group; alkoxycarbonyl group having 2 to 6 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group; carboxyl group; phenoxy group, Aryloxy group such as benzyloxy group; Alkylamino group such as diethylamino group and diisopropylamino group;
Aralkylamino groups such as dibenzylamino group and diphenethylamino group; haloalkyl groups such as trifluoromethyl group; hydroxyl group; phenyl group which may have a substituent,
An aromatic hydrocarbon ring group such as a naphthyl group; an aromatic heterocyclic group such as a thienyl group or a pyridyl group which may have a substituent.

Examples of the substituent that the aromatic hydrocarbon ring group and the aromatic heterocyclic group may have include a halogen atom such as a fluorine atom; an alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group; a vinyl group. An alkenyl group having 2 to 6 carbon atoms such as; a carbon number 2 such as a methoxycarbonyl group and an ethoxycarbonyl group
~ 6 alkoxycarbonyl group; C1-6 alkoxy group such as methoxy group, ethoxy group; aryloxy group such as phenoxy group, benzyloxy group; alkylamino group such as dimethylamino group, diethylamino group; acetyl group, etc. And an haloalkyl group such as a trifluoromethyl group; and a cyano group.

As R ^{201 to} R ²⁰⁶ , a hydrogen atom, an alkyl group, a halogen atom or a cyano group is more preferable. As R ²⁰⁴ , a cyano group is particularly preferable.
In the general formula (VI), as Ar ^{21 to} Ar ²⁵ , specifically, an aromatic hydrocarbon ring group such as a phenyl group which may have a substituent, a biphenyl group, a naphthyl group, or a thienyl group, pyridyl And aromatic heterocyclic groups such as groups. Among them, those having two or three condensed 5-membered ring, six-membered ring, five-membered ring and / or six-membered ring, or those having two or three bonded direct bonds thereof are preferable. Among the aromatic hydrocarbon ring group and the aromatic heterocyclic group, the aromatic hydrocarbon ring group is preferable.

Examples of the substituent which Ar ^{21 to} Ar ²⁵ may have include those described above as the substituent which R ^{201 to} R 2 ¹⁰⁶ may have when it is an aromatic hydrocarbon ring group or an aromatic heterocyclic group. And the same groups as. Preferred specific examples of the compound represented by the general formula (VI) are shown below, but the invention is not limited thereto.

[0134]

[Chemical 52]

[0135]

[Chemical 53]

As the hole blocking material, the above-mentioned general formula (VI) is used.
In addition to the mixed ligand complex of
A compound having at least one 2,4-triazole ring residue can also be used.

[0137]

[Chemical 54]

Specific examples of the compound having at least one 1,2,4-triazole ring residue represented by the above structural formula are shown below, but the invention is not limited thereto.

[0139]

[Chemical 55]

Although not described in the above structural formulas, the benzene ring and naphthalene ring in these compounds may further have a substituent. Examples of the substituent include the same groups as those described above as the substituent that R ^{201 to} R ²⁰⁶ may have when R ^{201 to} R ²⁰⁶ are an aromatic hydrocarbon ring group or an aromatic heterocyclic group. As the hole blocking material, a compound having at least one phenanthroline ring represented by the following structural formula can also be used.

[0141]

[Chemical 56]

Specific examples of the compound having at least one phenanthroline ring represented by the above structural formula are shown below, but the invention is not limited thereto.

[0143]

[Chemical 57]

For these compounds, the above 1, 2,
Similar to the case of the compound having a 4-triazole ring residue,
It may have a substituent other than those specified in the structural formula, and in this case, the substituent may be, for example, R ^{201 to} R ^206.
When the is an aromatic hydrocarbon ring group or an aromatic heterocyclic group, examples of the substituent that can be included include the same groups as those described above.

The compounds of the above hole blocking materials may be used alone in the hole blocking layer 6, or may be used by mixing two or more kinds thereof, if necessary. The thickness of the hole blocking layer 6 is usually 0.3 to 100 nm, preferably 0.5 to 50 nm.
nm. The hole blocking layer 6 can also be formed by the same method as the hole transporting layer 4, but a vacuum deposition method is usually used.

The cathode 8 has the hole blocking layer 6 and the light emitting layer 5
Plays a role of injecting electrons into. The material used for the cathode 8 may be the material used for the anode 2, but a metal having a low work function is preferable for efficient electron injection, and tin, magnesium, indium, calcium, Suitable metals such as aluminum and silver or alloys thereof are used. Specific examples thereof include low work function alloy electrodes such as magnesium-silver alloy, magnesium-indium alloy, and aluminum-lithium alloy.

The film thickness of the cathode 8 is usually the same as that of the anode 2. For the purpose of protecting the cathode made of a low work function metal, it is preferable to further stack a metal layer having a high work function and stable to the atmosphere on the cathode in order to increase the stability of the device.
For this purpose aluminum, silver, copper, nickel,
Metals such as chrome, gold and platinum are used.

For the purpose of further improving the luminous efficiency of the device, it is conceivable to provide an electron transport layer 7 between the hole blocking layer 6 and the cathode 8 as shown in FIG. The electron transport layer 7 is formed of a compound capable of efficiently transporting electrons injected from the cathode 8 toward the hole blocking layer 6 between the electrodes to which an electric field is applied. Therefore, the electron-transporting compound used in the electron-transporting layer 7 is a compound having a high electron injection efficiency from the cathode 8 and having a high electron mobility and capable of efficiently transporting the injected electrons. It is necessary.

As a material satisfying such a condition, 8
-A metal complex such as an aluminum complex of hydroxyquinoline (JP-A-59-194393), 10-hydroxybenzo
[h] Metal complexes of quinoline, oxadiazole derivatives, distyrylbiphenyl derivatives, silole derivatives, 3-or
5-hydroxyflavone metal complex, benzoxazole metal complex, benzothiazole metal complex, trisbenzimidazolylbenzene (US Pat. No. 5,645,948), quinoxaline compound (JP-A-6-207169), phenanthroline derivative (JP-A-5-331459). Gazette), 2-t-butyl
-9,10-N, N'-dicyanoanthraquinone diimine, n-type hydrogenated amorphous silicon carbide, n-type zinc sulfide, n-type zinc selenide and the like can be mentioned. Further, the above-mentioned electron transporting compound is doped with an alkali metal (JP-A-10-2.
No. 70171, Japanese Patent Application No. 2000-285656, Japanese Patent Application No. 2000-285657, etc.),
It is preferable because the electron transport property is improved.

The thickness of the electron transport layer 6 is usually 5 to 200 nm,
It is preferably 10 to 100 nm. The electron transport layer 7 is formed by stacking on the hole transport layer 6 by a coating method or a vacuum deposition method in the same manner as the hole transport layer 4. Usually, a vacuum vapor deposition method is used. Further, for the purpose of further improving the efficiency of hole injection and improving the adhesion of the entire organic layer to the anode 2, as shown in FIG. 3, an anode buffer is provided between the hole transport layer 4 and the anode 2. Inserting layer 3 is also done. By inserting the anode buffer layer 3, it is possible to obtain an effect that the driving voltage of the element in the initial stage is lowered and, at the same time, an increase in voltage when the element is continuously driven with a constant current is suppressed. The material used for the anode buffer layer 3 is required to have good contact with the anode 2 to form a uniform thin film and be thermally stable, that is, its melting point and glass transition temperature are high, and the melting point is 300 ° C. As mentioned above, the glass transition temperature is required to be 100 ° C or higher. Further, it has a low ionization potential, easy hole injection from the anode 2, and high hole mobility.

For this purpose, phthalocyanine compounds such as copper phthalocyanine (JP-A-63-295695), polyaniline (Appl. Phys. Lett., Volume 64, 124) have hitherto been used.
P. 5, 1994), Polythiophene (Optical Materials, 9
Vol., P. 125, 1998), organic compounds, sputtered carbon films (Synth. Met., Vol. 91, p. 73, 1997), metal oxides such as vanadium oxide, ruthenium oxide, molybdenum oxide. Material (J. Phys. D, 29, 2750, 1996)
Has been reported. In addition, a layer containing a low-molecular organic compound having a hole injecting / transporting property and an electron-accepting compound (Japanese Patent Laid-Open No. H11 (1999) -115242).
No. 251067, JP-A-2000-159221, etc.) or a layer formed by doping a non-conjugated polymer compound having an aromatic amino group or the like with an electron-accepting compound, if necessary (JP-A No. 1993-242242). 11-283750, JP 2000-36390 A, JP 2000-1501.
68, JP 2001-223084, etc.)
Are also preferable.

The anode buffer layer 3 can also be formed into a thin film in the same manner as the hole transport layer 4, but in the case of an inorganic material, a sputtering method, an electron beam evaporation method or a plasma CVD method is further used. The thickness of the anode buffer layer 3 formed as described above is usually 3 to 100 nm, preferably 5 to 50 nm.

Further, at the interface between the cathode 8 and the light emitting layer 5 or the electron transport layer 7, an extremely thin insulating film (film thickness: LiF, MgF ₂ , Li ₂ O, etc.)
Inserting 0.1 to 5 nm is also an effective method to improve the efficiency of the device (Appl. Phys. Lett., 70, 152,
1997; Japanese Patent Laid-Open No. 10-74586; IEEE Trans. Electro
n. Devices, 44, 1245, 1997). The structure opposite to that of FIG. 1, that is, the cathode 8, the hole blocking layer 6,
It is also possible to stack the light emitting layer 5, the hole transport layer 4, and the anode 2 in this order, and as described above, the organic electroluminescent element of the present invention is provided between two substrates, at least one of which is highly transparent. It is also possible. Similarly, it is also possible to stack in a structure opposite to the above-mentioned layer structure shown in FIGS. 2 and 3. Further, in addition to the layers shown in FIGS. 1, 2 and 3, any layer may be provided between the anode or cathode and the light emitting layer.

The present invention can be applied to any one of the organic electroluminescence device, a single device, a device having an arrayed structure, and a structure in which an anode and a cathode are arranged in an XY matrix. You can

[0155]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to the description of the following examples unless it exceeds the gist. Synthesis example 1

[0156]

[Chemical 58]

10 mL of ortho-dichlorobenzene was added to a mixture of 626 mg of 2-aminothiophenol and 983 mg of thianaphthene-2-carbonyl chloride, and the mixture was added under nitrogen.
The reaction was carried out at 190 degrees for 15 hours. After cooling to room temperature, the solvent was removed and purification by column chromatography was performed to obtain 1.1 g of white crystals. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 267.02 Synthesis example 2

[0158]

[Chemical 59]

40 mL of acetic acid was added to 4.3 g of 2-aminothiophenol and 5.0 g of 2-formylbenzofuran and reacted at 45 ° C. for 9 hours. After cooling to room temperature, the solution was neutralized with an aqueous sodium hydroxide solution, the resulting precipitate was filtered and washed with methanol to obtain 5.8 g of a white solid.
From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 251.04 Synthesis example 3

[0160]

[Chemical 60]

40 mL of acetic acid was added to 4.3 g of 2-aminothiophenol and 5.0 g of 2-formylbenzofuran and reacted at 45 ° C. for 9 hours. After cooling to room temperature, the solution was neutralized with an aqueous sodium hydroxide solution and extracted with toluene. Then, the extract was dried using potassium carbonate, the solvent was removed, and purification by column chromatography was performed to obtain 2.0 g of a white solid. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 264.07 Example 1

[0162]

[Chemical formula 61]

294 mg of the compound obtained in Synthesis Example 1 and 176 mg of iridium trichloride trihydrate were added to 2-ethoxyethanol.
10 mL of water (3 mL) was added, and the mixture was reacted under nitrogen at 120 ° C for 10 hours. After cooling to room temperature, the obtained precipitate was filtered and washed with methanol. After drying the obtained precipitate, 53 mg of sodium carbonate, 15 mL of 2-ethoxyethanol and 0.1 mL of acetylacetone were added, and the mixture was further reacted under nitrogen for 9 hours. The obtained precipitate was filtered, washed with methanol, and purified by column chromatography to obtain 306
mg red crystals were obtained. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 824.03 Example 2

[0164]

[Chemical formula 62]

550 mg of the compound obtained in Synthesis Example 2 and 352 mg of iridium trichloride trihydrate were added to 2-ethoxyethanol.
15 mL of water (5 mL) was added, and the mixture was reacted under nitrogen at 140 ° C for 10 hours. After cooling to room temperature, the obtained precipitate was filtered and washed with methanol. After the obtained precipitate was dried, 106 mg of sodium carbonate, 20 mL of 2-ethoxyethanol and 0.1 mL of acetylacetone were added, and the mixture was further reacted under nitrogen for 7 hours. The obtained precipitate is filtered, washed with methanol, and purified by column chromatography.
5 mg of red crystals were obtained. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 792.07 Example 3

[0166]

[Chemical formula 63]

582 mg of the compound obtained in Synthesis Example 3 and 352 mg of iridium trichloride trihydrate were added to 2-ethoxyethanol.
15 mL and 5 mL of water were added, and it was made to react under nitrogen at 120 degree for 6 hours. After cooling to room temperature, the obtained precipitate was filtered and washed with methanol. After drying the obtained precipitate, 106 mg of sodium carbonate, 20 mL of ethoxyethanol and 0.2 mL of acetylacetone were added, and the mixture was further reacted under nitrogen for 9 hours. The precipitate obtained is filtered, washed with methanol and purified by column chromatography to give 410
mg red crystals were obtained. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 818.14 Synthesis example 4

[0168]

[Chemical 64]

20 mL of ortho-dichlorobenzene was added to a mixture of 1.09 g of 2-aminophenol and 1.96 g of thianaphthene-2-carbonyl chloride, and the mixture was added under nitrogen to 170
The reaction was performed for 15 hours. After cooling to room temperature, the solvent is removed, purification by column chromatography is performed,
1.2 g of white crystals were obtained. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 251.04 Example 4

[0170]

[Chemical 65]

525 mg of the compound obtained in Synthesis Example 4 and 352 mg of iridium trichloride trihydrate were added to 2-ethoxyethanol.
10 mL of water (3 mL) was added, and the mixture was reacted under nitrogen at 140 ° C for 8 hours. After cooling to room temperature, the obtained precipitate was filtered and washed with methanol. After the obtained precipitate was dried, 106 mg of sodium carbonate, 20 mL of 2-ethoxyethanol and 0.2 mL of acetylacetone were added, and the mixture was further reacted under nitrogen for 7 hours. The precipitate obtained is filtered, washed with methanol and purified by column chromatography.
2 mg of red crystals were obtained. From the results of mass spectrum measurement of the obtained compound, it could be confirmed to be the target product. M / e: 792.07 Example 5 An organic electroluminescent device having the structure shown in FIG. 3 was produced by the following method.

A glass substrate 1 on which a transparent conductive film of indium tin oxide (ITO) was deposited to a thickness of 150 nm (manufactured by Geomatec Co., Ltd .; electron beam film-formed product; sheet resistance 15 Ω) was subjected to ordinary photolithography and hydrochloric acid etching. 2
The anode 2 was formed by patterning into a stripe having a width of mm. The patterned ITO substrate is cleaned in the order of ultrasonic cleaning with acetone, pure water, and ultrasonic cleaning with isopropyl alcohol, and then dried by nitrogen blow.
Finally, ultraviolet ozone cleaning was performed and the device was installed in a vacuum vapor deposition device. After rough evacuation of the above equipment with an oil rotary pump, an oil diffusion pump equipped with a liquid nitrogen trap until the degree of vacuum inside the equipment becomes 2 × 10 ^-6 Torr (about 2.7 × 10 ^-4 Pa) or less. Was evacuated using.

As a material for the anode buffer layer 3, copper phthalocyanine of the following structural formula is used.

[0174]

[Chemical formula 66]

Using a molybdenum boat, a vapor deposition rate of 0.
15nm / sec, vacuum degree 1.9 × 10 ^-6 Torr (about 2.6 × 10 ^-4 Pa),
A film having a thickness of 10 nm was formed on the anode 2. Then placed in a ceramic crucible placed in the above device, as shown below, 4,
4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl

[0176]

[Chemical formula 67]

[0177] The vapor deposition was performed by heating with a tantalum wire heater around the crucible. The temperature of the crucible at this time is 210 ~ 2
Control was performed in the range of 35 ° C. Degree of vacuum during vapor deposition 1.5 × 10 ^-6 Torr
(About 2.0 × 10 ⁻⁴ Pa), vapor deposition rate was 0.28 nm / sec, and a hole transport layer 4 having a film thickness of 60 nm was obtained. Subsequently, the organic iridium complex (T-1) obtained in Example 1 was prepared by using the following N-phenylcarbazole derivative (H-1) as a main component (host material) of the light emitting layer 5 and a sub-component (dopant). Were placed in different ceramic crucibles, and a film was formed by a two-source simultaneous vapor deposition method.

[0178]

[Chemical 68]

[0179]

[Chemical 69]

The crucible temperature of the compound (H-1) is 250 to 26.
The deposition rate was controlled to 0 nm and the deposition rate to 0.2 nm / sec.
Body (T-1) is controlled in the temperature range of 320-325 ℃, and the film thickness is 30
nm containing 5% by weight of iridium complex (T-1)
The light layer 5 was laminated on the hole transport layer 4. Degree of vacuum during vapor deposition
Is 1.3 x 10^-6Torr (about 1.7 × 10^-FourPa). further,
Example Compound (HB-12) as a hole blocking layer 6 in a crucible
Film thickness of 10 nm at a deposition rate of 0.17 nm / sec at a temperature of 246 ° C
It was laminated with. Vacuum degree during vapor deposition is 1.2 x 10 ^-6Torr (about 1.6 ×
Ten^-FourPa).

[0181]

[Chemical 70]

On the hole blocking layer 6, an aluminum 8-hydroxyquinoline complex represented by the following structural formula, Al (C ₉ H ₆ NO) _{3 is formed} as the electron transport layer 7.

[0183]

[Chemical 71]

Was vapor-deposited in the same manner. At this time, the crucible temperature of the aluminum 8-hydroxyquinoline complex is 285
Controlled in the range of up to 300 ° C, the vacuum degree during vapor deposition is 1.1 × 10 ^-6 T
orr (about 1.5 × 10 ^-4 Pa), deposition rate is 0.24 nm / sec and film thickness is 3
It was set to 5 nm. The substrate temperature during vacuum deposition of the above hole transport layer, light emitting layer, hole blocking layer and electron transport layer was kept at room temperature.

Here, vapor deposition up to the electron transport layer 7 was performed.
Once the element is taken out of the vacuum evaporation system into the atmosphere
As a mask for cathode deposition.
The shadow mask should be orthogonal to the ITO stripe on the anode 2.
Close to the device as shown, and set it in another vacuum evaporation system
Then, the vacuum degree inside the device is 2.4 × 10 in the same way as the organic layer.^-6Tor
r (approximately 3.2 x 10^-FourPa) exhausted until below. With the cathode 8
Then, first, add lithium fluoride (LiF) to molybdenum bo.
Deposition rate of 0.01 nm / sec, vacuum degree of 3.6 × 10 ^-6Tor
r (about 4.8 × 10^-FourPa) of the electron transport layer 7 with a film thickness of 0.5 nm.
The film was formed on top. Next, aluminum is similarly molybdenum
Heated by boat, deposition rate 0.37nm / sec, vacuum degree 7.7
× 10^-6Torr (about 1.0 x 10^-3Pa) aluminum film with a thickness of 80 nm
Then, a cathode layer was completed by forming a vacuum layer. The above two-layer cathode
The substrate temperature during vapor deposition of No. 8 was kept at room temperature.

As described above, an organic electroluminescence device having a 2 mm × 2 mm size light emitting area portion was obtained. The light emission characteristics of this device are shown in Table 1. In Table 1, the maximum emission luminance is the value at a current density of 0.25 A / cm ² , and the luminous efficiency / luminance / current / voltage is the value at a luminance of 100 cd / m ² . The maximum wavelength of the emission spectrum of the device was 650 nm, which was identified as being from the organic iridium complex (T-1). Chromaticity
It was CIE (x, y) = (0.53,0.40).

Example 6 Instead of the organic iridium complex (T-1) as a subcomponent of the light emitting layer, the organic iridium complex (T-) obtained in Example 2 was used.
An element was produced in the same manner as in Example 5 except that 2) was used. The light emission characteristics of this device are shown in Table 1. The maximum wavelength of the emission spectrum of the device was 658 nm, which was identified as being from the organic iridium complex (T-2). Chromaticity is CIE (x, y)
= (0.44,0.45).

[0188]

[Chemical 72]

Example 7 The organic iridium complex (T-3) obtained in Example 3 was used instead of the organic iridium complex (T-1) as a subcomponent of the light emitting layer.
A device was produced in the same manner as in Example 5 except that was used. The light emission characteristics of this device are shown in Table 1. The maximum wavelength of the emission spectrum of the device is 519 nm, and the organic iridium complex (T
-3). Chromaticity is CIE (x, y) = (0.2
8, 0.50).

[0190]

[Chemical formula 73]

Example 8 The organic iridium complex (T-4) obtained in Example 4 was used instead of the organic iridium complex (T-1) as a subcomponent of the light emitting layer.
A device was produced in the same manner as in Example 5 except that was used. The light emission characteristics of this device are shown in Table 1. The maximum wavelength of the emission spectrum of the device is 616 nm, and the organic iridium complex (T
-4). Chromaticity is CIE (x, y) = (0.5
It was 1,0.41).

[0192]

[Chemical 74]

Example 9 As an auxiliary component of the light emitting layer, an organic iridium complex (T-
A device was manufactured in the same manner as in Example 5 except that (5) was used (three-way simultaneous vapor deposition). The light emission characteristics of this device are shown in Table 1. The maximum wavelength of the emission spectrum of the device is 650 nm,
It was identified to be from the organic iridium complex (T-1). The chromaticity was CIE (x, y) = (0.69,0.30), and the color purity was significantly improved as compared with Example 5.

[0194]

[Chemical 75]

Example 10 N-phenylcarbazole derivative as the main component of the light emitting layer
Aluminum used in the electron transport layer 7 instead of (H-1)
8-hydroxyquinoline complex, (Al (C₉H₆NO) ₃)
A device was produced in the same manner as in Example 5 except that the above was used. this
The emission characteristics of the device are shown in Table-1. Emission spectrum of device
Has a maximum wavelength of 653 nm, and the organic iridium complex (T-
It was identified as from 1). Chromaticity is CIE (x, y) = (0.70,
0.29), the color purity is significantly improved as compared with Example 5.
Was done. The current density of this device is 0.25A / cm²DC drive with
Then, when the stability of the device was evaluated, 48 seconds of this device
The brightness ratio after that (brightness after 48 seconds / initial brightness) is 0.96.
It was good.

[0196]

[Chemical 76]

Comparative Example 1 A device was prepared in the same manner as in Example 10 except that the organic iridium complex (T-6) shown below was used instead of the organic iridium complex (T-1) as a subcomponent of the light emitting layer. . The light emission characteristics of this device are shown in Table 1. The maximum wavelength of the emission spectrum of the device is 610 nm, and the organic iridium complex (T-6)
Was identified as As in Example 10, this element was driven by DC at a current density of 0.25 A / cm ² and the stability of the element was evaluated. The luminance ratio after 40 seconds (luminance after 40 seconds / initial luminance) was 0. 88, more unstable than in Example 10.

[0198]

[Chemical 77]

Comparative Example 2 A device was prepared in the same manner as in Example 10 except that the platinum complex (T-7) shown below was used instead of the organic iridium complex (T-1) as a subcomponent of the light emitting layer. The light emission characteristics of this device are shown in Table 1. The maximum wavelength of the emission spectrum of the device is 65
1 nm, identified as coming from a platinum complex (T-7). The chromaticity was CIE (x, y) = (0.71, 0.29), which was a good color purity, but the luminous efficiency was low as compared with Example 10.

[0200]

[Chemical 78]

[0201]

[Table 5]

[0202]

Example Synthesis Example 5

[0203]

[Chemical 79]

50 mL of acetic acid was added to 4.1 g of 2-aminothiophenol and 3.3 g of 2-furfural, and the mixture was reacted at 40 ° C. for 6 hours. After cooling to room temperature, the solution was neutralized with an aqueous solution of sodium hydroxide and extracted with dichloromethane. Thereafter, the extract was dried using potassium carbonate, the solvent was removed, and purification by column chromatography was performed to obtain 3.2 g of a white solid. From the mass measurement results of the obtained compound, it could be confirmed that the compound was the desired product. M / e: 215 Example 11

[0205]

[Chemical 80]

473 mg of the compound obtained in Synthesis Example 5 and 352 mg of iridium trichloride trihydrate were added to 2-ethoxyethanol.
20 mL of water (5 mL) was added, and the mixture was reacted under nitrogen at 120 ° C for 10 hours. After cooling to room temperature, the obtained precipitate was filtered and washed with methanol. After drying the obtained precipitate, 212 mg of sodium carbonate, 20 mL of 2-ethoxyethanol and 0.2 mL of acetylacetone were added, and the mixture was refluxed under heating for 9 hours under nitrogen. The obtained precipitate was filtered, washed with methanol, and purified by column chromatography to obtain 73 mg of red crystals. From the mass measurement results of the obtained compound, it could be confirmed that the compound was the desired product. M / e: 720 Synthesis example 6

[0207]

[Chemical 81]

50 g of acetic acid was added to 4.1 g of 2-aminothiophenol and 3.8 g of 2-methylthiophenecarbaldehyde, and the mixture was reacted at 40 ° C. for 10 hours. After cooling to room temperature, the solution was neutralized with an aqueous solution of sodium hydroxide and extracted with dichloromethane. Thereafter, the extract was dried using potassium carbonate, the solvent was removed, and purification by column chromatography was performed to obtain 3.2 g of a white solid. From the mass measurement results of the obtained compound, it could be confirmed that the compound was the desired product. M / e: 231 Example 12

[0209]

[Chemical formula 82]

509 mg of the compound obtained in Synthesis Example 6 and 352 mg of iridium trichloride trihydrate were added to 2-ethoxyethanol.
20 mL of water (5 mL) was added, and the mixture was reacted under nitrogen at 120 ° C for 10 hours. After cooling to room temperature, the obtained precipitate was filtered and washed with methanol. After the obtained precipitate was dried, 424 mg of sodium carbonate, 20 mL of 2-ethoxyethanol and 0.4 mL of acetylacetone were added, and the mixture was heated under reflux for 12 hours under nitrogen. The obtained precipitate was filtered, washed with methanol, and purified by column chromatography to obtain 91 mg of red crystals. From the mass measurement results of the obtained compound, it could be confirmed that the compound was the desired product. M / e: 752

Example 13 The organic iridium complex (T-8) obtained in Example 11 was used in place of the organic iridium complex (T-1) as a sub ingredient of the light emitting layer, and copper phthalocyanine of the anode buffer layer 3 was used. Instead, a non-conjugated polymer compound having an aromatic amino group (PB-1; homopolymer, weight average molecular weight 28,000, number average molecular weight 16000, Tg = 171).
A device was produced in the same manner as in Example 5 except that a layer obtained by spin coating (C) with the electron-accepting compound (A-1) was used. The light emission characteristics of this device are shown in Table 2. The maximum wavelength of the emission spectrum of the device was 614 nm, which was identified as being from the organic iridium complex (T-8). Chromaticity is CIE (x,
y) = (0.65, 0.34).

[0212]

[Chemical 83]

[Spin coating conditions for forming anode buffer layer 3] Solvent Ethyl benzoate coating solution concentration 2 [wt%] PB-1: A-1 10: 1 (weight ratio) Spinner rotation speed 1500 [rpm] Spinner rotation Time 30 [sec] Drying condition 100 ℃ 1 hour Film thickness 30nm

Example 14 Instead of the organic iridium complex (T-1) as a subcomponent of the light emitting layer, the organic iridium complex (T-
An element was produced in the same manner as in Example 5 except that 9) was used. The light emission characteristics of this device are shown in Table 2. The maximum wavelength of the emission spectrum of the device was 611 nm, which was identified as being from the organic iridium complex (T-9). Chromaticity is CIE (x, y)
= (0.60,0.34).

[0215]

[Chemical 84]

[0216]

[Table 6]

[0217]

As described in detail above, according to the present invention,
In particular, a novel organic iridium complex capable of improving color purity in long-wavelength light emission, high efficiency of light emission, and long life of the element, and an organic electroluminescent element of long life and high light emission efficiency using this organic iridium complex are provided. Provided.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of an organic electroluminescence device of the present invention.

FIG. 2 is a schematic cross-sectional view showing another example of the embodiment of the organic electroluminescent element of the present invention.

FIG. 3 is a schematic cross-sectional view showing another example of the embodiment of the organic electroluminescent element of the present invention.

[Explanation of symbols]

1 substrate 2 anode 3 Anode buffer layer 4 Hole transport layer 5 Light emitting layer 6 Hole blocking layer 7 Electron transport layer 8 cathode

Continued front page    (72) Inventor Yoshiharu Sato             1000 Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa             Within Mitsubishi Chemical Corporation F term (reference) 3K007 AB03 AB04 AB11 DB03 FA01                 4H050 AA01 AA03 AB91 WB11 WB13                       WB21

Claims (6)

[Claims] 1. An organic iridium complex represented by the following general formula (i). [Chemical 1] (In the formula, m represents the number of ligands L, and is 0, 1 or 2. L represents any bidentate ligand. Ring A is a 5-membered aromatic compound having at least one hetero atom. Group B represents a heterocyclic group and may have a substituent, ring B represents a 5-membered aromatic heterocyclic group containing a nitrogen atom, and may have a substituent.
The group contained in A and the group contained in ring B may be bonded to each other to form a condensed ring containing ring A and ring B. In addition, ring A,
An arbitrary substituent is bonded to the carbon atom at the α-position of the hetero atom contained in ring B. ) 2. A compound represented by the general formula (i) is
The organic iris of claim 1 represented by the general formula (ii).
Complex. [Chemical 2] (Where X and Y¹Are independently sulfur atom and oxygen source
Child, or -NR¹⁰⁵-(R ¹⁰⁵: Hydrogen atom or
Represents a substituent). L represents an arbitrary bidentate ligand. m
Represents the number of ligands, and is 0, 1, or 2.
R¹⁰¹, R¹⁰⁵Each independently has a hydrogen atom and a halogen atom
Child, alkyl group, alkenyl group, alkynyl group, aral
Kill group, cyano group, amino group, acyl group, alkoxy group
Rubonyl group, aryloxycarbonyl group, alkoxy
Group, carboxyl group, hydroxyl group, mercapto group, alkyl
Thio group, arylthio group, sulfonyl group, silyl group,
Ryl group, phosphino group, aromatic hydrocarbon ring group or aromatic
Group represents a heterocyclic group, each of which has a substituent
You may stay. R¹⁰²~ R¹⁰⁴Is an independent halogen source
Child, alkyl group, alkenyl group, alkynyl group, aral
Kill group, cyano group, amino group, acyl group, alkoxy group
Rubonyl group, aryloxycarbonyl group, alkoxy
Group, carboxyl group, hydroxyl group, mercapto group, alkyl
Thio group, arylthio group, sulfonyl group, silyl group,
Ryl group, phosphino group, aromatic hydrocarbon ring group or aromatic
Group represents a heterocyclic group, each of which has a substituent
You may stay. In addition, R¹⁰¹And R¹⁰², Or R¹⁰³And R¹⁰⁴
May be bonded to each other to form a ring. 3. A compound represented by the general formula (i) is
The organic iris according to claim 1, which is represented by the general formula (iii).
Um complex. [Chemical 3] (In the formula, Y²And Z are each independently a sulfur atom or an oxygen source.
Child, or -NR¹¹⁰-(R ¹¹⁰: Hydrogen atom or
Represents a substituent). L represents an arbitrary bidentate ligand. m
Represents the number of ligands, and is 0, 1, or 2. R¹⁰⁷
And R¹¹⁰Each independently has a hydrogen atom and a halogen atom
Child, alkyl group, alkenyl group, alkynyl group, aral
Kill group, cyano group, amino group, acyl group, alkoxy group
Rubonyl group, aryloxycarbonyl group, alkoxy
Group, carboxyl group, hydroxyl group, mercapto group, alkyl
Thio group, arylthio group, sulfonyl group, silyl group,
Ryl group, phosphino group, aromatic hydrocarbon ring group or aromatic
Group represents a heterocyclic group, each of which has a substituent
You may stay. R¹⁰⁶, R¹⁰⁸And R¹⁰⁹Each independently
Halogen atom, alkyl group, alkenyl group, alkynyl
Group, cyano group, aralkyl group, amino group, acyl group,
Lucoxycarbonyl group, aryloxycarbonyl group,
Alkoxy group, carboxyl group, hydroxyl group, mercapto
Group, alkylthio group, arylthio group, sulfonyl group,
Silyl group, boryl group, phosphino group, aromatic hydrocarbon ring
Group or aromatic heterocyclic group, both of which
It may have a substituent. In addition, R¹⁰⁶And R¹⁰⁷, Or
R¹⁰⁸And R¹⁰⁹Each of which is bonded to form a ring
Good. 4. An organic electroluminescent device comprising a substrate, an anode, a light emitting layer, and a cathode, which are sequentially stacked, wherein the light emitting layer contains a compound represented by the general formula (i). And an organic electroluminescent device. 5. The light emitting layer contains a host compound having a hole injecting / transporting property or an electron injecting / transporting property, and the host compound is doped with a compound represented by the general formula (i). The organic electroluminescent element according to claim 4, wherein 6. The organic electroluminescent device according to claim 4, further comprising a hole blocking layer between the light emitting layer and the cathode.